Crimping tool



F. R. CHIRCO CRIMPING TOOL June 30, 1970 2 Sheets-Sheet l Filed Jan. 26, 1968 Non .0 mg; f my. m

www? NHNW I I f W J N N M June 30, 1970 P. R. cHlRco 3,517,539

CRIMP ING TOOL Filed Jan. 26, 1968 2 SheeLs-Sheet 2 1NVENTOR.

United States Patent O 3,517,539 CRIMPING TOOL Peter R. Chirco, Utica, Mich., assigner to Huck Manufacturing Company, Detroit, Mich., a corporation f Michigan Filed Jan. 26, 1968, Ser. No. 700,824 Int. Cl. B21d 17/02 U.S. Cl. 72-414 10 Claims ABSTRACT OF THE DISCLOSURE A tool for crimping fasteners by utilizing relative translational motion between two opposed ja-Ws. The tool end portion which carries the crimping jaw members includes a rotatable feature -which increases the versatility of the tool. The jaw members are provided with a relief for ow of displaced metal.

The present invention relates to crimping tools and more particularly to a crimping tool of the type for setting fasteners including a pin and a collar and in which the tool will apply a preload to the fastener as a result of crimping deformation of the collar.

'It is an object of the present invention to provide a novel crimping tool.

It is another object of the present invention to provide a novel crimping tool for setting two-piece fasteners including a pin and a collar in -which the collar is to be set with a desired preload.

'Other objects, features, and advantages of the present invention will become apparent from the subsequent description and the appended claims, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a longitudinal cross-sectional View of the tool 0f the present invention;

FIG. 2 is a sectional view to enlarged scale taken substantially along the line 2-2;

FIG. 3 is a sectional view to enlarged scale taken substantially along the line 3-3;

FIG. 4 is a blown up view of that portion of the tool enclosed by the dot-dashed line 4; and

FIG. 5 is a sectional view taken substantially along the line 5'-5.

The tool is generally indicated by the numeral and includes a tubular housing member 12 -which has an enlarged cylinder 14 which terminates at one end in an enlarged, partially threaded counterbore 16 and at the other end in a reduced diameter eccentric bore 18. This eccentric bore 18, in turn, is in coaxial communication with a reduced diameter through opening 20'. A piston 22 has a large head portion 24 generally matably, slidably located within the cylinder 14 and is hydraulically sealed around its periphery by means of a pair of annular seals 26 located in seal receiving grooves 28. The piston 22 has an eccentric rod portion 30 which extends axially and eccentrically relative to the head portion 24 and extends through the eccentric bore portion 18 and reduced diameter bore 20. The piston 22 is mounted for reciprocation within the cylinder 14 lwhich is closed at its rearward end by a cap 32 which is held by a retaining nut 34 threaded into the counterbore 16. The cap 32` is pe* ripherally sealed by a seal 34 located in a groove 36. The cap 32 has a throughbore 38 in communication with Patented June 30, 1970 a threaded portion 4t] which is adapted to receive a conventional hydraulic fitting. A relief portion 42 is in communication with the passageway 38 and permits fluid flow into the cylinder 14 with the piston 22 in its rearwardmost position as shown. Upon application of uid pressure from the source (not shown) through the portion 40 and passageway 38, pressurized fluid in the head end of the cylinder 14 moves the piston 22 forwardly against the bias of a return spring 44 which is located about the rod portion 30 and abuts against the head portion 24 and has its opposite end in engagement with the end wall of the reduced diameter cylinder or bore 18. Upon release of the uid pressure applied to the head end of the cylinder 14, the piston 22 will be returned to its original position (as shown) by the bias of spring 44.

The forward end of the housing 12 terminates in a reduced diameter portion 46 which has an annular groove 47 located therein. An outer or xed anvil 48 has a cylindrical portion 50 with a throughbore 52 similar to the bore 20 and is located over the outer extremity of the rod portion 30 of the piston 22. The forward portion 5t) is provided with an annular groove 54. A pair of semicircular locking rings 56 and 58 have generally C-shaped cross sections and are located with the legs of the C in the grooves 47 and 54 whereby the lixed anvil 48 will be secured from axial movement to the housing member 12. An annular retaining sleeve 60 is located over the semicircular sleeves 56 and 58 to hold them together and a retaining ring 62 holds the ring 60 from axial movement. Thus in the assembly as shown, the fixed jaw assembly 48 is axially xed to the cylinder housing 12. Note, however, that the xed jaw 48 is rotatable relative to the housing assembly 12 which serves a purpose to be described.

The iixed jaw member 48 has a generally longitudinally extending through-slot 64 which is in line with the bore 52 through the rearward portion 50.

A movable anvil 66 is generally slidably located Within the slot 64 and is supported for axial movement relative to the xed anvil 48. The movable anvil 66 terminates in a reduced diameter pin portion 468 which is slidably movably engageable within a bore 70 at the forwardmost end of the rod portion 30` of the piston 22. A coil spring member 72 is located Within the slot 64 and has one end in a pocket at the forward end of the slot 64 in the xed anvil 48 and has its opposite end in a pocket in the movable anvil 66. Spring 72 is biased to maintain the movable anvil 66 in its rearwardmost position in the slot 64; hence, the spring 72 also maintains the pin portion `68 in the bore 70. Note that the movable anvil 66 can move independently of the piston 22. As the piston 22 is moved forwardly by the application of fluid pressure in the head end of the cylinder 14, the rod portion 30 by virtue of the engagement against the rearward end of the movable jaw 66 will move the jaw 66 forwardly in the slot 64. Upon the release of uid pressure in the head end of the cylinder 114 and upon return of the piston 22 to its rearward position (as shown) by virtue of the spring 44, the force of the rod portion 30 against the movable jaws 66 urging the jaw `66 in its forward position, is removed. However, the jaw 66 will follow the rod portion 30 in its rearward movement by virtue of the bias of the spring 72. Thus the movable jaw 66 can move relatively to the piston 22. Thus as the r fixed anvil 48 is rotated relative to the housing 12, by

virtue of the connection provided by the elements 56, 58, 60 and 62, the movable anvil 66 can also rotate by virtue of the interconnection provided by pin portion 68, bore 70 and spring 72. The rotatable feature increases the versatility of the tool. With the eccentric rod portion 30, the tool can be used in areas in which there is a minimum amount of clearance in the area immediately behind the fastener being set. On the other hand, obstructions may appear at random locations relative to the fastener to be set. In this instance the fixed anvil 48 and movable anvil 66 can be rotated so as to place the entire tool in the most adavntageous clearance relationship with the obstruction.

As previously noted, the tool 10 is specifically adapted for use in setting a two-piece fastener including a pin and collar in which the collar could have been previously threadably secu-red to the pin to hold the workpieces together. The addition of crimping can increase the preload between the fastener and the workpieces; this results from the iiow of material caused by crimping. It is desirable, however, that the collar be crimped at a specific location. To insure this, a pair of locating pins 74 are secured to the movable jaw 66 and extend into throughbores 76 in the fixed jaw in the outer forward wall of the fixed jaw 48. The locating pins 74 are positioned at a preselected location relative to the crimping surfaces of the iixed and movable jaws to properly position the crimping surfaces relative to the collar. The xed and movable jaws 48 and 66, respectively, are provided with confronting crimping surfaces 78 and 80, respectively. The crimping surfaces 78 and 80` are generally of a attened V shape in cross section each having a flat portion on its radially inner end which flat portion tapers to an increased width.

It is contemplated that the tool 10 will be utilized in crimping collars which generally have a circular shape and hence the crimping surfaces 73 and 80 generally extend circularly. However, in view of the fact that material is being displaced in the crimping operation it has been found that some means should be provided in the crimping surfaces 78 and 80 to permit good metal flow and enhance the provision of a preload.

Looking now to FIGS. 2, 4 and 5, the fixed jaw 48 and movable jaw 66 are shown in their opened position prior to crimping a collar. The collar is indicated in phantom in FIG. 5 relative to crimping surface 78 (crimping surface '80 is identical). Note that the general contour of the crimping surfaces 78 and 80 are circular and together extend for approximately 360 and While slightly smaller in diameter generally match the contour of the collar. However, the circumferential ends 81 of the crimping surface 78 are of substantially increased radius which are smoothly blended to permit good flow of displaced collar material. By providing good iiow the collars can be crimped without being substantially distorted to an ovalshape which would decrease preload. Also the relief at ends 81 of crimp surface 78 (and similar relief at ends 83 on surface 80) provides an area for metal to flow and aids in keeping metal from flowing between and being trapped between the ends of jaws 48 and 66 which trapped metal would inhibit further crimping.

In addition to the clearance provided at opposite ends of the fixed and movable jaws 48 and 66 it has been found that advantageous results are also obtained by providing a relief generally in the center of the crimping surfaces 78 and 80 via grooves 82 and 84, respectively. The grooves 82 and 84 permit areas for flow of metal displaced and enhances the crimping action resulting in a good preload. In view of the yfact that only two jaws are used, it has been found that the relief provided by the grooves v82 and 84 is quite important.

In the tool 10, it is important that the crimping surfaces 78 and 80 be moved substantially in translation, i.e., with no cooking or rotation, and also that the movement be such that the surfaces 78 and 80 are substantially maintained in direct alignment with each other. In order to provide the above alignment and translational movement, the movable jaw 66 is provided with a fiat guide and reaction plate member 86 (see FIGS. l and 3) which rides in tight engagement against the edges 88 of the side walls of the fixed anvil 48. The use of the iiat plate member 86 in engagement with the substantial area of the edges 88 provides accurate guiding of the movable jaw 66 insuring translational movement and accurate alignment. In addition, the substantial contact area between the flat plate member 86 and the guide edges 88 reacts the large forces Which occur during crimping. This substantial contact area resists the tendency for the jaws 78 and v80 to pivot or rotate relative to each other as a result of the crimping forces and helps to keep the motion of the crimping surfaces 78 and 80 translational during crimping. This is important since a less effective crimp and less effective preload in the crimped collar results if substantial pivoting or rotation occurs during crimp.

The extent or depth of the crimp is determined by the total movement of the piston 22. The total movement of the piston 22 is set by an adjustable stop pin 90 which is threaded into the forward wall of the cylinder housing 12 and extends partially into the cylinder 14. The point of engagement of the head portion 24 with the stop pin 90 determines the forwardmost movement of the piston 22 and thus determines the extent or depth of the crimp which preferably is set such that the opposed crimped surfaces are generally along a common circle having the diameter of crimping surfaces 78 and 80.

While it will be apparent that the preferred embodiment of the invention disclosed is well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modication, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

1. A crimping tool for crimping a collar having a generally circular contour'comprising: piston means including a piston actuable for reciprocation in a cylinder, jaw means including a pair of jaw members, at least one of said jaw members being connected to said piston means for relative movement toward and away from the other of said jaw members in response to movement of said piston, each of said pair of jaw members having a projecting crimping portion extending generally arcuately and being ared radially outwardly at the opposite ends to provide clearance areas for the flow of displaced material from crimping, a relief groove in said center portion of said crimping portion to provide an area for the ow of displaced material from crimping.

2. The crimping tool of claim 1 including connecting means connecting said jaw means for rotation relative to said piston, said crimping portion extending generally semicircularly in its center with a radius no greater than the radius of the collar.

3. The crimping tool of claim 2 with said other of said jaw members being axially iixed to said cylinder and with said one of said jaw members being supported for axial movement by said piston, said connecting means including first rotational means connecting said other jaw member for rotation relative to said cylinder and second rotational means connecting said one jaw member for rotation relative to said piston, said radius of said center portion being less than the radius of the collar.

4. The crimping tool of claim 3 with said second rotational means comprising a pin and a socket.

5. The crimping tool of claim 2 with said piston having a rod portion eccentric with a head portion and with said connecting means connecting said jaw means generally in line with said rod portion.

6. The crimping tool of claim 4 further including locating means extending between said jaw members a preselected distance from said projecting, crimping portion.

7. The crimping tool of claim 4 including iiuid actuating means connected to one end of said cylinder for actuating said piston for causing crimping and including a spring member biased against said piston for causing return of said piston.

8. The tool of claim 7 including a second spring member urging said jaw members apart.

9. The tool of claim 1 including a flat plate secured to one of said jaw members and in sliding engagement over a substantial area with edges ofthe other of said jaw members whereby pivoting of said jaw members during crimping is minimized.

10. The tool of claim 8 including a at plate secured to said one of said jaw members and in sliding engagement over a substantial area with edges of the other of said jaw members whereby pivoting of said jaw members during crimping is minimized, said piston having a rod portion eccentric with a head portion and with said connecting means connecting said jaw means generally in line with said rod portion, locating means extending between 2,968,202 1/1961 Evans 72-410 3,174,323 3/1965 Over 72-412 3,181,341 5/1965 Thornton 72--410 3,182,485 5/1965 Sund 72-410 3,212,316 10/1965 Smith 72-412 CHARLES W. LANHAM, Primary Examiner G. P. CROSBY, Assistant Examiner U.S. C1. X.R. 72-416, 453 

